How do I reverse a pushbutton logic with a switch?

Thread Starter

vifyrv

Joined Mar 15, 2023
4
What is the simplest way to reverse the logic of a switch? What I have are audio levels running to a jack or speakers. I figured out how to simply add a Sanwa arcade button to interrupt the flow when it is not pressed and simply complete the circuit when it is pressed.

The question: is there a simple logic gate that I could implement to add a switch to the circuit so when the switch is on, the button works normally: gate opens when pressed, and when the switch is off, using the same button: gate is always opened, but closed when pressed.

Simplified
Switch on: sound is off but on when button is pressed
Switch off: sound is always on but turns off when button is pressed

Basically I want to toggle the same button between being a gate or a mute.

Any thoughts?
 

Alec_t

Joined Sep 17, 2013
14,417
Welcome to AAC.
I figured out how to simply add a Sanwa arcade button to interrupt the flow when it is not pressed and simply complete the circuit when it is pressed.
Please post a schematic to show us how. Is the switch currently wired simply in series with the audio signal, or is it providing a logic signal for on/off control of an audio processing device/stage ?
 

Thread Starter

vifyrv

Joined Mar 15, 2023
4
Welcome to AAC.

Please post a schematic to show us how. Is the switch currently wired simply in series with the audio signal, or is it providing a logic signal for on/off control of an audio processing device/stage ?
It's simply in series.
 

MrAl

Joined Jun 17, 2014
11,734
What is the simplest way to reverse the logic of a switch? What I have are audio levels running to a jack or speakers. I figured out how to simply add a Sanwa arcade button to interrupt the flow when it is not pressed and simply complete the circuit when it is pressed.

The question: is there a simple logic gate that I could implement to add a switch to the circuit so when the switch is on, the button works normally: gate opens when pressed, and when the switch is off, using the same button: gate is always opened, but closed when pressed.

Simplified
Switch on: sound is off but on when button is pressed
Switch off: sound is always on but turns off when button is pressed

Basically I want to toggle the same button between being a gate or a mute.

Any thoughts?

The relay sounds like a good idea.
If you have low level and low power signals and they do not have to be perfectly distortion free then you may be able to use analog switches.
 

LesJones

Joined Jan 8, 2017
4,228
If you can get a version of your arcade button with changeover contacts and that together with a single pole changeover switch should do what you require. If you can obtain a changeover version of your button I will post a diagram of how to connect them.

Les.
 

Ron314

Joined Mar 14, 2023
21
Have you ever been in a house with a pair of 3-way switches used for the light? Are you talking about that level of simplicity?
 

MrAl

Joined Jun 17, 2014
11,734
Keep in mind he wants to use the same button and change the NO (normally open) operation to NC (normally closed) operation.
That's how i interpreted his first post anyway, and the push button is a SPST pushbutton switch.
Can you do that with a simple switch?
Maybe, but show your schematic.
A question might be can he change out the original pushbutton switch to a SPDT type. That would change this.
 

LesJones

Joined Jan 8, 2017
4,228
Hi MrAl, If the TS insists that he uses the existing push button then my suggestion is excluded. I don't think it is possible to meet the TS's requirements with just an added switch. He does not say if he has power available to drive a relay or some logic ICs. (An XOR gate such as a CD4030 and a quad bilateral switch such as a CD4066.)
If the TS could tolerate some attenuation it could be done with just a DPDT switch and a resistor. Some information on the signal source impedance and the input impedance of the destination would be required to suggest a suitable value for the resistor.
160323.jpgIn position A of the DPDT switch the push button would rout the signal through when pressed.
In position B the push button would short the signal to ground.

Les.
 

Thread Starter

vifyrv

Joined Mar 15, 2023
4
Actually I found a Cherry D44x switch that has NC and NO. I'll wire a switch before them and that should work! Thanks for the help!
 

MrAl

Joined Jun 17, 2014
11,734
Actually I found a Cherry D44x switch that has NC and NO. I'll wire a switch before them and that should work! Thanks for the help!
Hi,

Yes that is a SPDT switch as suggested previously.
That will of course be simple to implement as noted previously.
" A question might be can he change out the original pushbutton switch to a SPDT type. That would change this. "
 
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